Ok, some of my impressions...

1. The graphics are definitely better, but when viewing the action from a distance, it doesn't make much of a difference. I'll be upgrading my hardware soon, so I'll then be able to perceive the full impact of this improvement.

2. For some reason, it seems a bit harder to keep track of what's going on. This is probably just because I'm just not used to the changes.

3. I happen to like the musical score. The voice acting is average in quality and out of place at times. For example, selecting a unit causes that unit to announce its type, and soldiers scream "we're under attack!" when attacked. These features seem like attempts to mimic other strategy games, and are out of place in the Total War series.

4. The Battle of Trebia is quite easy; I won a "heroic victory" the first time. As has been noted, skirmishers run away too soon when on skirmish mode and the Poeni infantry are missing their spears.

5. The green triangles beneath selected troops really are too intrusive. Banners turning white for routed units also look rather silly; such measures weren't necessary in prior TW games.

6. I agree that the fights seemed rushed. I had hoped for longer melees, rather than shorter ones. When combined with the inherent difficulty in keeping track of everything that's going on, this is less than ideal.

That's about it for now. I enjoyed the demo overall, but wish some things were different. Oh well.